diff --git a/mm/swapfile.c b/mm/swapfile.c index 3c1172b53436..043645e7f0b5 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -204,8 +204,16 @@ static void discard_swap_cluster(struct swap_info_struct *si, #ifdef CONFIG_THP_SWAP #define SWAPFILE_CLUSTER HPAGE_PMD_NR + +#define swap_entry_size(size) (size) #else #define SWAPFILE_CLUSTER 256 + +/* + * Define swap_entry_size() as constant to let compiler to optimize + * out some code if !CONFIG_THP_SWAP + */ +#define swap_entry_size(size) 1 #endif #define LATENCY_LIMIT 256 @@ -1192,18 +1200,7 @@ void swap_free(swp_entry_t entry) /* * Called after dropping swapcache to decrease refcnt to swap entries. */ -static void swapcache_free(swp_entry_t entry) -{ - struct swap_info_struct *p; - - p = _swap_info_get(entry); - if (p) { - if (!__swap_entry_free(p, entry, SWAP_HAS_CACHE)) - free_swap_slot(entry); - } -} - -static void swapcache_free_cluster(swp_entry_t entry) +void put_swap_page(struct page *page, swp_entry_t entry) { unsigned long offset = swp_offset(entry); unsigned long idx = offset / SWAPFILE_CLUSTER; @@ -1212,39 +1209,41 @@ static void swapcache_free_cluster(swp_entry_t entry) unsigned char *map; unsigned int i, free_entries = 0; unsigned char val; - - if (!IS_ENABLED(CONFIG_THP_SWAP)) - return; + int size = swap_entry_size(hpage_nr_pages(page)); si = _swap_info_get(entry); if (!si) return; - ci = lock_cluster(si, offset); - VM_BUG_ON(!cluster_is_huge(ci)); - map = si->swap_map + offset; - for (i = 0; i < SWAPFILE_CLUSTER; i++) { - val = map[i]; - VM_BUG_ON(!(val & SWAP_HAS_CACHE)); - if (val == SWAP_HAS_CACHE) - free_entries++; - } - if (!free_entries) { - for (i = 0; i < SWAPFILE_CLUSTER; i++) - map[i] &= ~SWAP_HAS_CACHE; - } - cluster_clear_huge(ci); - unlock_cluster(ci); - if (free_entries == SWAPFILE_CLUSTER) { - spin_lock(&si->lock); + if (size == SWAPFILE_CLUSTER) { ci = lock_cluster(si, offset); - memset(map, 0, SWAPFILE_CLUSTER); + VM_BUG_ON(!cluster_is_huge(ci)); + map = si->swap_map + offset; + for (i = 0; i < SWAPFILE_CLUSTER; i++) { + val = map[i]; + VM_BUG_ON(!(val & SWAP_HAS_CACHE)); + if (val == SWAP_HAS_CACHE) + free_entries++; + } + if (!free_entries) { + for (i = 0; i < SWAPFILE_CLUSTER; i++) + map[i] &= ~SWAP_HAS_CACHE; + } + cluster_clear_huge(ci); unlock_cluster(ci); - mem_cgroup_uncharge_swap(entry, SWAPFILE_CLUSTER); - swap_free_cluster(si, idx); - spin_unlock(&si->lock); - } else if (free_entries) { - for (i = 0; i < SWAPFILE_CLUSTER; i++, entry.val++) { + if (free_entries == SWAPFILE_CLUSTER) { + spin_lock(&si->lock); + ci = lock_cluster(si, offset); + memset(map, 0, SWAPFILE_CLUSTER); + unlock_cluster(ci); + mem_cgroup_uncharge_swap(entry, SWAPFILE_CLUSTER); + swap_free_cluster(si, idx); + spin_unlock(&si->lock); + return; + } + } + if (size == 1 || free_entries) { + for (i = 0; i < size; i++, entry.val++) { if (!__swap_entry_free(si, entry, SWAP_HAS_CACHE)) free_swap_slot(entry); } @@ -1268,14 +1267,6 @@ int split_swap_cluster(swp_entry_t entry) } #endif -void put_swap_page(struct page *page, swp_entry_t entry) -{ - if (!PageTransHuge(page)) - swapcache_free(entry); - else - swapcache_free_cluster(entry); -} - static int swp_entry_cmp(const void *ent1, const void *ent2) { const swp_entry_t *e1 = ent1, *e2 = ent2;